Jaguars

[MechEng83]

Originally Posted by MichelB

Most everyone is switching to Talons. This seems to be the way to go for the upcoming season.

What data do you have to support this claim?

[geomapguy]

Originally Posted by MechEng83

What data do you have to support this claim?

I second this, many teams are still all-victor or all-jaguar.

[brennonbrimhall]

Originally Posted by MechEng83

What data do you have to support this claim?

I personally have no data to back MichelB's claim up, but Talons have been a significantly more pleasant experience to work with than Victors or Jaguars. Not only are they reliable and pretty indestructible, but they have the smallest footprint too. And most of the time, you don't need a fan on them. As a programmer, they feature a more linear response, so I don't have to compensate for that in my code.

It's my opinion that unless I'm using CAN, Talons are the way to go.

That being said, IFI has definitely addressed the community's constructive feedback on its products, but I'm not well-versed in the new(er) Victor 888 or updated Jaguars to comment on this.

[Jacob Bendicksen]

Originally Posted by brennonbrimhall

I personally have no data to back MichelB's claim up, but Talons have been a significantly more pleasant experience to work with than Victors or Jaguars. Not only are they reliable and pretty indestructible, but they have the smallest footprint too. And most of the time, you don't need a fan on them. As a programmer, they feature a more linear response, so I don't have to compensate for that in my code.

Agreed. I don't have any hard evidence to back it up, but they're just nicer to work with. Smaller, lighter, hardier, and unless they're on a drive motor they don't need a fan. They're also close to impossible to smoke with metal shavings unless you're trying.

[MichelB]

Originally Posted by MechEng83

What data do you have to support this claim?

I, personally have not worked with Talons but the concensus seems to be that they are easier to work with and a better piece of hardware overall.

[IndySam]

We will never use a Jaguar again, they just caused way too many problems.

We used a mix of talons and victor 888 last year and were very happy with the performance of both. Unless there are rule changes we will do the same this year.

[MrBasse]

How can everyone claim that Talons are tougher than another speed controller. We have been using the same Victors for four years straight and haven't had a failure yet. Talons have only been around for a year, so time will tell. Jaguars on the other hand...We've cooked 9 of those (one with actual flame coming out of the vents) and avoid them as much as possible unless we run out of Victors. I'm fairly sure that I can get smoke to come out of one just by looking at it, but it might also have something to do with our shop environment...

In my view, availability of the Talon during season has been the biggest issue with it, so we have yet to get to play with one. I'm excited to get one, but we don't have the funds to pick up enough to use without mixing speed controllers.

[MichaelBick]

While we wouldn't use jaguars on the comp bot, I've heard they are really good for protos because of they build in PID and current sensing.

[Anupam Goli]

You can purchase additional jaguars here: http://www.vexrobotics.com/217-3367.html

I always thought the CAN bus capabilities of the jaguar were very interesting and if the hardware was more reliable, I'd use the jaguar more often.

[MechEng83]

We ended up using all 3 controllers at various points on our 2013 robot. (Though only 2 at any one time.)

Jaguars are great because of following reasons (and we utilize each one):

Current sensing
Internal PID control
Forward/Reverse Limit Switches
CAN

Jaguars have the following drawbacks (each of which we've experienced):
Relatively low current limits (Though it seems to have been raised with the latest firmware update)
Poor CAN (physical) connection robustness
Highly sensitive to swarf (metal debris) -- though the new ones have a conformal coating.

[Pault]

Originally Posted by MechEng83

Jaguars have the following drawbacks (each of which we've experienced):
Relatively low current limits (Though it seems to have been raised with the latest firmware update)
Poor CAN (physical) connection robustness
Highly sensitive to swarf (metal debris) -- though the new ones have a conformal coating.

Don't forget about a giant footprint.

And all those extra features can be a disadvantage too, because you now have the temptation to use them when often you would be better off without them.

In 2012 (rookie year) my team used Jaguars with CAN. I will just say that even the word CAN now instills fear into the hearts of our veteran students. In 2013 we wanted to use Talons, but the sold out, so instead we used Victor 888s, and had no complaints. This year we have bought 4 talons to put on the electronics test bed we are building, and if they really are as good as everyone says they are we will put them on our 2014 robot.

[yash101]

We used Victors last year, and kept cooking them, (because our motors kept shorting out, damaging their FETs. We haven't been having those problems anymore, because our shooter is disabled so we barely use it. Victors, themselves, are quite nice. They were lightweight last year, compared to jaguars, and they work nicely. I do not have too much experience with Jaguars, but it seems though the feature set is quite great. The CAN interface is nice, along with the PWM interface. These can be networked through an RS232 interface too! There are a lot more features that I won't list, but here's the manual: http://content.vexrobotics.com/docs/...e_20130215.pdf. As mentioned before, a big problem in these motor controllers is their maximum continuous current. In the product page (http://www.vexrobotics.com/217-3367.html), here is the specs table:

Never Limit Progressive Limit Immediate Limit
Pre v107 40A 50A 60A
v107 40A 50A 92A


Here are the Talon specs:
Page: http://www.andymark.com/Talon-p/am-2505.htm

Input voltage: 6-28 VDC
Continuous current: 60 A (above 40A continuous we recommend adding this fan)
Peak current: 100 A
Input PWM signal: 0.9-2 ms @ 333 Hz
Input resolution: 10-bit (1024 steps)
Output resolution: 10-bit (1024 steps)
Output switching frequency: 15 kHz
Talon SR: Synchronous sign-magnitude rectification
Smart LED, blinks proportional to throttle, now with obvious change from 99% throttle to 100%
Simple calibration
User selectable brake/coast
4% neutral dead band
Linear throttle response

I hope this helped. This is a comparison between Talons and Jaguars.

[Jared]

The two most important features of a speed controller are reliability and cost. We don't want to worry about swapping out controllers after a match, and we really want to avoid failures during the match. Reliability is also important because we use previous years speed controllers on the practice robot. This year, our practice bot had victors from 2003 and 2004 that have already been used on at least two robots. Victors are the only controller with this type of reliability. They are also the cheapest.

As for the extra features, I think they're a waste. We end up wrapping the speed controller class to add a few utilities, so it's easy to add a pidcontroller and and the function to make the output linear. The jaguars don't really have any features that can't be done on the crio.

[yash101]

I agree. Victors will take a lot of abuse before failing. The only failures we had were because of a shorted motor. If they added temperature sensors to the MOSFETS, they could allow it to do an emergency shutdown before damage!

[MechEng83]

Originally Posted by Jared

The jaguars don't really have any features that can't be done on the crio.

Please let me know where the current sensing feature is on the cRIO. My team has been unaware of this feature.